Dhirendra Jaiswar

The descaling is done in 3 steps:-

1. Prepare 6-10 % solution of descalent BWDBC-25. The diluted solution is then continuously circulated for 3-8 hours depending upon thickness of the scale deposit.
2. The temperature of the solution should not exceed 40C during circulation as it may evaporate. The strength of the circulating solution should be maintained by periodically adding descalent BWDBC-25. Maintain PH of circulating solution 2-4 throughout the cleaning period.
When concentration of calcium magnesium in the solution no longer rise or iron contents rise substantially or acidity ceases to fall the reaction may be taken as descaling completed.
3. When the treatment has been completed drain the unit as quickly as possible fill it with fresh water and drain again. Flush the system with an alkaline solution to neutralize the chemical effect drain off alkaline solution and flush the system with fresh water.

The dosage will depend upon the quality of feed water. In case where softened water is used. A dosage of 20-30 ppm will ensure scale free boiler tubes for long periods. In case of 100% condensate such as in sugar mills boilers about 15- 20 ppm is adequate.

Keep the container tightly closed away from direct heat and sunlight. Wear rubber gloves goggles and shoes when handling. Do not get in eyes on skin or on clothing. In case of contact wash with plenty of fresh cold water if necessary seek medical attention.